Synthesis and Applications of Fatty Acid Estolides

Fatty acid estolides are fatty acid oligomers, where the fatty acid chains are coupled to each other via secondary ester linkages. Fatty acid estolides can be produced by the acid-catalysed polymerization of unsaturated fatty acids or by the chemical or enzymatic condensation of hydroxy fatty acids. Fatty acid estolides have gathered significant interest as biobased and biodegradable components of biolubricants and cosmetics and as building blocks for polyurethanes. This chapter discusses the production and (potential) applications of this interesting class of molecules. After introducing the synthetic methodologies through which fatty acid estolides and their constituent hydroxy fatty acid building blocks can be produced, we discuss a range of (potential) applications for these estolides.